I have recently decided to foster, and possibly keep, some fish for a friend while they move. Now, I have a little problem. I have lots of fish, and not sure which can be with which and how much room the foster-fish need. So, experts help me mix and match my fishie crew and see who should be where?

I have-
TANKS:
20 gal
5 gal
2 gal
and another 2 gal.

FISH:
4 Neon Tetras - blue, teal, orange, red. All fosters.
1 Pleco - I think hes a male? Foster fish.
1 Male Veiltail betta [pretty aggressive when he mated, and flares at the mirrors, had him for 6 months]
1 Male Crowntail [who almost never flares at the mirror, probably flared twice since I've had him, which is about 5 months.]
1 Female Veiltail betta [not very aggressive when mating, doesnt flare at the other betta, the crowntail, and their tanks are very near each other.]

EQUIPMENT:
One large filter for takes 10+ gal
One small filter for 10 or less gal
One heater

Willing to get more of whatever I need, but trying to work with my tanks that I have.

The Pleco needs to go unless it's a bristlenose or a clown.. I would put the Pleco in the 20G for now until he gets rehomed. Plecos produce too much ammonia. The tetras will need to be in the 20G, too. The tetras will be a little stressed with only 4 so I'd get 2 more or so. They're schooling fish and need room to swim. All the fish I have mentioned should be in the 20G. This tank should have the large filter.

Divide the 5G to house the 2 male bettas since you can't house males with females at all unless it's a 100+ tank. This tank should have the small filter. Make sure it's baffled so the fish can swim. QT a male in one of the 2G tanks so the other male wont get sick. Double the dividers and block it with plants since the VT is ultra aggressive.

The female should go in the last 2G. :D

You will need 2 more heaters, how many watts is the current heater you have? Brand?

Why thank you. Even if the Pleco is small, they still have a pretty high bio-load. Oh, and I live in MD! Not in Baltimore, though. There are hardly any MD'ers here, it's quite sad since it's a great place. Lol

Thanks LeBronthebetta! I was thinking the same about the pleco. My friends had the pleco and tetras in one 2 gal tank. I wanted to rehome him but there's no fish lovers here that would probably take care of him. Anyone want a pleco? Haha. I don't know too much about them so I don't know what kind it is. could you tell from a pic?

Common pleco's will eat other fish, they only eat algae when they are younger. Be careful with that one, as they get older they do eat and crave meat. My old common pleco cleaned out our tank and ate all our fish, we moved him into a larger tank with two larger goldfish and after a month both goldfish had become pleco food. He now lives with someone else in a monster fish tank with larger fish but has still taken a bite out of bass fish.